Bicycle frame



FIG. 1 is a front perspective view of a bicycle frame showing my new design.

FIG. 2 is a left side elevation view thereof.

FIG. 3 is a right side elevation view thereof.

FIG. 4 is a front elevation view thereof.

FIG. 5 is a top plan view thereof; and,

FIG. 6 is a bottom plan view thereof.

The broken lines which define the boundaries of the claimed design form no part thereof. The broken lines shown within the front tube in FIGS. 5 and 6 are for illustrative purposes only and form no part of the claimed design. 

The ornamental design for a bicycle frame, as shown and described. 